Have you ever blurted out, "Wow, that guy is just so...so..." and then were left floundering with nothing to say? Well, it's not always your fault. English doesn't have words for every situation, or even the ones that happen every damned day.
Fortunately, other languages usually do. And since we already borrow words from them (just recently we've taken "schadenfreude," the German word for pleasure in someone else's misfortune) here's a few that we need to pick up right away:

Means:
A beautiful girl... as long as she's being viewed from behind.
Say you're in a bar, and you look over to see the most incredible sight you've ever seen: a tall, slim woman with a waterfall of dark copper hair, an ass like a fresh peach in shrinkwrap and legs all the way down to the floor. You saunter over, lean against the bar next to her and give her your best line: "I got a boner just looking at you, can I buy you a drink?"
That's when she turns to look at you.

Bile rises in your throat. It's hard to say which is worse--is it the mole sprouting hair on her cheek? The yellow tombstone teeth? The eyepatch? The wiry black hair sprouting out from between her breasts?
Congratulations, you have just been a victim of bakku-shan: a girl that looks attractive from behind, but not from the front. It's a more sophisticated variant of the American frat boy's butter-face (as in everything about her is hot, "but her face") that makes room for attractive women with weird neck tattoos, while at the same time allowing the speaker to avoid giving everyone within ear-shot douche-chills.
Truly the Japanese have a talent for coming up with words to describe common social situations so succinctly. Like they did with "bukkake."
9
Espirit d'escalier (French)

Means:
When you think of the perfect verbal comeback... much too late.
So you're at a social gathering and a friend, in front of your peers, points at your chest and says, "Good sir, is that your shirt, or did you just vomit on your torso?"
The sting of his insult renders you wordless. Then, mere moments later, just as you've exited the room to the cacophony of humiliating laughter that will be the soundtrack to the rest of your life, you come up with the perfect comeback. Only moments later, but still much, much too late (note, the correct comeback was, "Neither, this is a special shirt created by scientists at the FBI to identify pedophiles, as it is specifically designed to offend their sensibilities to the point that they must comment. You will now be added to a sex offender registry").

"Oh, excuse me, it looks like you dropped your pride. Better grab it."
The French have come up with a term for your belated wit, Esprit d'escalier. Literally "the wit of the staircase," meaning you couldn't think up anything sassy until walking down the stairs afterward.